1. Field of the Invention
The present invention relates generally to pistons for internal combustion engines and more particularly to pistons made of steel.
2. Related Art
In their continuing efforts to improve power production and fuel efficiency, many engine manufactures are incorporating advanced technologies such as direct injection, turbo-chargers and super-chargers into their gasoline-fueled engines. Often, these and other advanced technologies improve the engine's performance by increasing the pressures and temperatures of combustion within the engine's cylinder bore. However, conventional aluminum pistons may not be able to perform adequately in these increased temperatures and pressures. In order to withstand and perform at the increased combustion temperatures and pressures, some piston manufacturers have taken to using steel to make their pistons. In order to cool their steel pistons, many piston manufacturers incorporate one or more oil galleries into their piston bodies to retain a cooling oil at or near the upper crown portions of their piston bodies.